Grinding disk



FIG. 1 is a front elevational view of a grinding disk;

FIG. 2 is a right side elevational view of the grinding disk;

FIG. 3 is a top plan view of the grinding disk;

FIG. 4 is a bottom plan view of the grinding disk; and,

FIG. 5 is a perspective view of the grinding disk. 

The ornamental design for a grinding disk, as shown and described. 